Coloration of textile materials



United States Patent 3,116,104 COLORATIUN 0F TEXTHJE MATERIALS Henry Charles Qlpin and .loseph Anthony Bright, Spondon, England, assiguors to British Celanese Limited, a corporation of Great hritain No Drawing. Filed Nov. 30, 1955, Ser. No. 550,209 Claims priority, application Great Britain Dec. 3, 1954 16 Claims. (Cl. 357) This invention relates to the colouring of textile and other materials of cellulose acetates of high acetyl value e.g. acetyl value above 59% calculated as acetic acid. For convenience, cellulose acetates having acetyl value above 59% are hereinafter referred as cellulose triacetates.

Textile material of acetone-soluble cellulose acetate (which has an acetyl value in the region of 54%) can be dyed from aqueous baths to full shades with a wide range of disperse dyes and, moreover, the dyeing can be effected in a reasonable time, for example 1-2 hours, without using temperatures above about 85 C. The latter is about the highest temperature at which acetone-soluble cellulose acetate can be processed in conventional aqueous dyeing and scouring baths without risk of loss or" lustre. In the case of textile material of cellulose acetate of high acetyl value and in particular cellulose triacetate we have observed that dyeing is in general much slower and less complete than in the case of acetone-soluble cellulose acetate dyed under similar conditions of time and temperature. This is more particularly the case with those disperse dyes which only yield full shades on acetone-soluble cellulose acetate in a reasonable time, say in 1 hour, when dyeing is effected at above 75 C. These dyes includes some which are particularly valuable on account of the good light and wash fastness of their shades.

We have now found that when dyeing textile material of cellulose acetate of high acetyl value, and particularly textile material of cellulose triacetate, with dyes in aqueous media, temperatures above 100 C. and particularly above 105 or 110 C. can be used with great advantage. The advantages obtainable by dyeing at such temperatures as compared with dyeing at conventional dyeing temperatures lie not only in respect of much greater rate of dyeing but also in respect of improved wash fastness of the resulting dyeings.

The advantages obtainable may be illustrated by reference to the case of dyeing knitted fabric of yarns made by dry spinning a solution of cellulose acetate of 61.5% acetyl value in a mixture of methylene chloride and methyl alcohol (ratio about 93:7 by volume), the dye being Eastman Fast Blue GLF, or the dye 1:8-dihydroxy-5-nitro-4- (p-beta-hydroxyethyl-anilido)-anthraquinone in the form of a disperse dye powder containing about 30% of the colouring matter. These dyes dye acetone-soluble cellulose acetate in blue shades of excellent fastness to light and gas-fading; they require a dyeing temperature of at least 75 C. in order to obtain full shades in 1 hour. A series of dyein gs (A) were made by dyeing portions of the above cellulose triacetate fabric with 0.5, 1.0, 2.0, 3.0 and 4.0% respectively of the disperse dye powder. Dyeing was effected from a 50:1 aqueous bath using 1 g. per litre of Pentrosan A2 (a non-ionic product) as dispersing agent, the dyeing temperature being 100 C. and the duration 1 hr. during which time the material was kept in motion in the dye liquor. A second series of dyeings (series B) were conducted in the same manner except that the temperature was 135 C. This necessitated the use of a closed dyeing vessel, the pressure being that corresponding with the vapour pressure of the dye liquid, namely about 32 lbs. per sq. in.

None of the samples were noticeably affected in the matter of lustre. It was found that for a given percentage of dye the amount of dye taken up, as evidenced by the shade, was far greater in the case of series B than in the case of series A. Thus 1% of dye applied as for series B (135 C.) gave about the same depth of shade as 4% of dye applied as for series A at 100 C. The various dyed materials were subjected to wash fastness test No. 2 of the Society of Dyers and Colourists. In this test a portion of the dyed material was sewn to a portion of fabric of acetone-soluble cellulose acetate and subjected for 1%. hours at c. to the acetion of an aqueous solution containing 2 gr. per litre of soap. The amount of dye which had been transferred to the undyed acetone-soluble cellulose acetate was then assessed by comparison with the Society of Dyers and Colourists Geometric Grey Scale for staining assessment-see Journal of the Society of Dyers and Colourists, August 1953, pages 286-289. It was found that the staining due to the specimens dyed at 135 C. was less by about one point on the Grey Scale than staining due to the dyeings of the same depth made at C. A still further improvement in wash fastness, as evidenced by the degree of staining on undyed cellu lose acetate, can be secured by giving the dyed materials a short scour in soap solution.

Similar results may be obtained when the fabric is of cellulose acetate yarns made by melt spinning a cellulose acetate of about 61.5% acetyl value.

In carrying out the new dyeing process, the contacting of the aqueous dye liquor with the cellulose acetate textile material may be effected in various ways depending inter alia on the form of the material. Thus loose staple fibre may be treated in a circulatory type of dyeing machine in which the dye liquid is pumped repeatedly through a mass of the staple fibre. The machine must of course be pro vided with steam or other heating means to raise the dye liquor to the required temperature and must be capable of resisting the pressures developed at these temperatures. Hanks of yarn may similarly be treated while packed in the same type of machine. Again yarn wound into packages on suitable perforated supports may be treated in a circulatory type of machine in which the liquid can be pumped through the packages of yarn. In this case also the necessary heating means must be provided and the machine must resist the steam pressure developed. Fabrics likewise may be processed in package form, for example while wound in layers on suitable perforated supports so that the liquid can be pumped through the layers of fabric. Preferably however, in the case of fabric the latter is passed repeatedly through the dye liquor as is the case when using a conventional jig or winch. Thus a jig may be used which is adapted to be run into an autoclave. Provision is made for driving the rolls while the winch is Within the autoclace, for example by means of shafts carried through a wall of the autoclave and provided with dogs or the like adapted to engage and drive corresponding dogs or the like on the ends of the shafts carrying the jig rollers. In operation the winch may be loaded with the fabric and the necessary dye liquor, run into the autoclave, the latter closed, and saturated pressure steam introduced to raise the temperature of the dye liquor to the required point. Advantageously the autoclave is provided with a valve which may be kept open during the initial stages of introduction of steam so that air may be driven out prior to permitting the temperature and pressure to build up to the required degree. The fabric is repeatedly carried through the dye liquor from roll to roll by operating the driving means in the manner customary in the case of jig dyeing machines. The dyeing temperature may be from C. or C. upwards, e.g. to C., or higher.

Another method of carrying out the colouring process of the invention is to impregnate the textile material with the requisite amount of dye and thereafter to subject the impregnated material to the action of saturated e.g. moist steam at a temperature above 100 C. and of course under the requisite pressure. Thus fabrics of cellulose acetate of high acetyl value may be padded or printed with an aqueous preparation, thickened if desirable, containing the colouring matter and thereafter steamed with saturated steam in a pressure steamer, for example a cottage steamer. Here again the temperature may range from say 110 C. or 115 C. up to 135 C. or more and the steam pressure range from 6 lbs. to lbs. or more per sq. in.

The greatest advantages of the invention are secured when the dyes employed are of low solubility in plain water or water containing soap. Such dyes include some of the disperse dyes largely employed for the dyeing of acetone-soluble cellulose acetate. These dyes are often regarded as substantially insoluble in water, but all are in fact soluble to at least a small extent in water or soap solution and reliance is placed on this small degree of solubility for the transfer of the dye to the textile material. Normally the solubility of the dye is such that, with the ratios of goods to liquor normally employed, say from 10 to 1 to to 1, only a small proportion of the dye is in solution in the dyeing liquid at any one time the remainder being present in the form of finely dispersed solid particles. If the solubility of the dye is such that a substantial part is in solution in the dye liquid at 100 C. e.g. if the solubility of the dye in the dye liquid exceeds about 10 mg. per litre at 80 C. or 100 C., relatively little advantage is secured by dyeing at higher temperatures in accordance with the invention. If on the other hand the dye is of lower solubility in the dye liquid, and especially if only a small proportion of the dye is soluble in the dye liquid at 100 C., then very considerable advantage may be secured by processing the cellulose acetate of high acetyl value at temperatures above 100 C. in accordance with the invention. The blue dye 1:8-dihydroxy-5-nitro-4- (p-beta-hydroxyethyl-anilido)-anthraquinone already referred to is a dye of this character and as already indicated it is very advantageous to effect dyeing therewith at temperatures substantially above 100 C. Other disperse dyes behaving similarly in this respect are 1-amino-4-phenylamino-anthaquinone, 1-amino-4-paratolyl-amino-anthra quinone, 1-hydroxy-4-phenylamino-anthraquinone, l-hydroxy-4-paratolylamino-anthraquinone, 1-methylamino-4- phenylamino-anthraquinone, and the product obtainable by condensing meta-aminophenyl-methyl carbinol with a mixture of 2 parts of dinitro-anthra-rufin and one part of dinitro-chrysazin so as to replace one of the nitro groups by a meta-aminophenyl-methyl carbinol radical; all these dyes are of the kind which when applied from an aqueous bath, only yield full shades on acetone-soluble cellulose acetate in one hour when the dyeing temperature is at last 75 C. Still other dyes in the same category are 2- nitro-diphenylamine-4-sulphon-anilide, 4-nitro-2-methylsulphonyl 4 (N-ethyl-N-beta-difluoroethyl-amino)-azobenzene, 4-nitro-2-methylsulphonyl)-4-(N-beta-hydroxyethyl-N-beta-difluoroethyl-amino)-azobenzene, 4-m'tro-2- methylsulphonyl 2 methyl-4-(N-dihydroxypropyl-N- beta difiuoroethyl-amino)-azobenzene, 4-nitro-2-methylsulphonyl 4 (N-beta-hydroxyethyl-N-gamma-trifiuoropropylamino -azobenzene, 4-nitro-2-methylsulphonyl-Z'- methyl 4' (N betahydroxyethyl-N-beta-triiluoroethylamino)-azobenzene, the azo dyes obtainable by coupling diazotised 6-ethoxy-2-amino-benzthiazole with N-beta-hydroxyethyl N beta-difluoroethyl-aniline or N-beta-hydroxyethyl N-beta-trifluoroethyl-aniline, Eastman Fast Red GLF, Eastman Fast Brilliant Red ZB-GLF, and the azo dye obtainable by coupling diazotised 2-chlor-4- nitro-aniline with N:N-di(beta-hydroxyethyl)-meta-toluidine. The new process is of particular value when the solubility of the dye in plain Water at 80 C. is not greater than about 2 mg. per litre, and especially when the solubility is not greater than about 0.2 mg. per litre.

A very useful black shade can be obtained by utilising suitable mixtures of the above mentioned dyes. For ex ample a good black shade can be obtained in the following manner. Five parts of a fabric knitted from yarn of cellulose acetate of about 61.5% acetyl value and made by a dry-spinning process as hereinbefore indicated is dyed in a pressure vessel from a 40:1 aqueous bath containing on the Weight of the cellulose acetate, 1.5% of 2-nitro-diphenylarnine-4-sulphonanilide, 2.25% of Eastman Fast Red GLF or of 4-nitro-2-methylsulphonyl-2-methyl-4'-(N- betahydroxyethyl N beta-trifluoroethyl-amino)-azoben- Zene (disperse dye powder of 30% strength), and 2% of the blue dye mixture obtained by condensing a 2:1 mixture of dinitroanthrarufin and dinitrochrysazin with metaaminophenyl-methyl-carbinol. The dyebath also contains as dispersing agent 0.5 gr. per litre of Albatex P0, a sulphonated long-chain-alkyl benzimidazol. The material is entered cold and the temperature raised to 130135 C. in the course of 1 /2 hours and dyeing continued for a further hour. After cooling below C. the material is removed and washed off with water.

The process of the invention can also be utilised for the dying of cellulose triacetate textile material with unreduced vat dyes, for example undigoid dyes, e.g. 5 z 7 5 7 -tetrabromoindigo and 4: 4-dimethyl-6 6-dichloro-thio-indigo, and vat dyes of the anthracene series, e.g. 1 5-di(benzoylamino -anthraquinone, dibenzanthrone, di methoxydibenzanthrone, pyranthrone, dibenzpyrenequinone, and the dye obtainable by the ring closure of the benzanthronyl-l-amino anthraquinone made by condens- 7 ing Bz-l-chlorobenzanthrone With l-aminoanthraquinone.

The new process may also be used for the colouring of cellulose triacetate textile materials with aqueous dispersions of free leuco compounds of the above and other vat dyes. In this case of course the material should subsequently be oxidised to convert the leuco compound of the vat dye to the parent vat dye.

Other dyes which can be applied by the new process are the WEMCI-lflSOlllblfi metallised dyes whether of the azo or other series. The metallised dyes are preferably free from sulphonic groups and preferably also from carboxylic groups.

The commercial dyes Orasol Navy Blue RB, Orasol Red 28 and Orasol Yellow 3R all of which are metallised azo dyes may be applied in this way. Further a mixture of these three dyes in a ratio of about 2:2:1 can be applied in order to obtain a very satisfactory black. The dyes may be applied for example to a loose staple fibre of cellulose acetate of acetyl value about 61% in a circulatory pressure dyeing machine using a liquor to good ratio of about 15:1 and a dyeing temperature of 135 C. The dye liquor may consist of water, the requisite dye or dyes and a small proportion of a suitable dispersing agent, for example 0.5 gr. per litre of Turkey red oil, 0.5 gr. per litre of Albatex P0 (a sulphated longchain-alcohol) or 0.5 gr. per litre of soap or 1 gr. per litre of Pent-rosan A2 (a non-ionic dispersing agent) or Dispersol VL (a fatty alcohol ethylene oxide condensate). For a blue shade 4 to 6% of Orasol Navy Blue RB may be used or for black a mixture of 6% Orasol Navy Blue RE, 6% of Orasol Red 23 and 3% of Orasol Yellow 3R, the percentages being based on the weight of the cellulose acetate. After charging the dyeing machine with the material and dye liquor, the temperature may be raised to 130135 C. in the course of 30 mins. and dyeing continued for one hour at this temperature; following this the temperature may be lowered to below 100 C. and the material washed and dried.

The cellulose acetate fibre referred to in this specific embodiment of the invention may as before he a product made by dry-spinning a solution of cellulose acetate of about 61% acetyl value in a mixture of methylene chloride and methyl alcohol (ratio about 93 to 7 by volume); again it may be a product made by melt-spinning a cellulose acetate of similar acetyl value.

Metallised dyes are compounds of dyes of mordant dyeing character with metals such as chromium, copper, cob-alt, nickel, and other metals, particularly those of atomic weight between 50 and 66. In the metallised dye the metal is in complex combination, that is to say the metallised dye does not, with water, yield ions of the metal. The apparent dyes are advantageously azo dyes, particularly azo dyes in which an azo group unites two carbon atoms one of which is directly attached to a carbon atom carrying a hydroxyl group while the other is directly attached to a carbon atom which carries a hydroxyl group, a carboxyl group or a carboxy-methoxy group, -OCH COOH but preferably a hydroxyl group. The carbon atoms attached to the azo groups and the adjacent carbon atoms carrying the hydroXyls or other groups referred to above may form part of benzene or heterocyclic rings or of open chains. In the metallised products, the metal is attached to the dye molecule via the groups carried by the carbon atoms adjacent to the azo group and probably also via the azo group itself; in consequence the said groups are no longer available to impart substantial solubility in water or aqueous alkalies. The metallised dyes are, as indicated above, preferably free from sulphonic groups and even from carboxyl groups other than any which may have taken part in lake formation with the metal. They may be such as are substantially insoluble or very little soluble in water or aqueous alkalies. This is the case for instance with the azo dye made by coupling di-azotised 4-nitro-2-arninophenol with 1-pheny1-3-me-thyl-5-pyrazolone or with 2- naphthol and then converting the product into a compound of chromium or other lake-forming metal, the compound containing about 1 atom of metal to 1 molecule of parent dye. The metallised azo dyes may, however, be such as are somewhat soluble in water or aqueous alkalies, for example due to the presence of groups which, unlike sulphonic groups or even carboxyl groups, are not more than weakly acid in character. Such groups are for instance sulphonamide groups, (e.g. the group SO NH or SO NR R where R and R are alkyl groups, sulphone groups (eg SO .CH or hydroxyl groups, the said hydroxyl groups being so disposed with respect to other groups as not to invite combination with the metallising metal. Such dyes are chromium compounds (containing about 1 atom of chromium to 1 molecule of dye) of the azo dye from 1 molecule of diazotised 4-nitro-2-aminophenol or other ortho-aminophenol and 1 molecule of 1:5-dihydroxy-naphthalene, and the azo dyes obtainable by coupling diazotised 4-nitro- Z-aminophenol or 6-chloro-4-nitro-2-aminophenol with 1- (meta-sulphonamido-phenyl) -3-methyl-5-pyrazolone or with acetoacetic anilide-meta-sulphonamide.

Metallised products of greater solubility in water may also be obtained by conducting the metallisation with less than 1 atom of metal, e.g. chromium or cobalt, to each molecule of dye. This expedient and that of using a parent dye containing a non-metallisable hydroxyl group or a sulphonamide group (as mentioned above) may be used simultaneously. Such more soluble products are for instance those obtained by chroming 2 molecules of the azo dye from diazotised 4-nitro-2-aminophenol and acetoacetic anilide with about 1.2 atoms of chromium in the form of alkali metal chromo-salicylate or by a similar chroming of the azo dye from diazotised 4-methyl-6-nitro-2-aminophenol and l-phenyl-S-methyl-S- pyrazolone or from diazotised 4-nitro-2-aminophenol and aceto-acetic-anilide-meta-sulphonamide.

A considerable number of the dyes of the foregoing character are available on the market under the trade names Orasol (Ciba), Cibalan (Ciba) and Irgalan tt The present invention is not restricted to the use of metallised dyes derived from azo dyes. Metallised dyes of other kinds may be employed. For example, metal lakes of alizarin and its derivatives or metal lakes of azo methine dyes containing groups which permit lake formation may be used. Such azo methine dyes include those obtainable by condensing an ortho-hydroxy-aromatic aldehy'de, e.g. salicyl aldehyde, or nitro-salicyl aldehyde, with an aromatic ortho amino-hydroxy-compound, e.g. ortho amino-phenol or a nuclear substitution product thereof. These azo methine dyes may be used for instance in the form of chromium, nickel or cobalt compounds, including such as contain about 1 atom of metal to two molecules of dye. An example of such a product is the cobalt compound of the azo methine compound made by condensing S-nitro-salicyl-aldehyde with 2-amino-phenol, the said compound containing about 1 atom of cobalt to 1 molecule of dye, or the chromium compound of the azomethine compound from salicyl aldehyde and Z-aminophenol, the said compound containing about 1 atom of chromium to 2. molecules of dye.

The colouring of cellulose triacetate textile materials with the metallised dye may, as already indicated, be effected by subjecting the material to the action of an aqueous medium containing the dye at a temperature above C. The aqueous medium may be Water alone but preferably contains a dispersing agent, for example Turkey red oil, a sulphated higher fatty alcohol, a sulphonated long-chain'alkyl-benzimidazol, or a non-ionic dispersing agent of the kind obtainable by condensing several molecular proportions of ethylene oxide with one molecular proportion of a higher fatty alcohol or higher fatty acid or castor oil. The presence of an electrolyte, eg a neutral alkali metal salt such as sodium chloride or sodium sulphate is often advantageous, particularly in the case of those metallised unsulphonated dyes which are soluble in water.

The new method can be used not only for the application of dyes to cellulose acetate of high acetyl value but also for the application of azo dye components, Whether diazo components or coupling components, which can subsequently be converted to an azo dye on the material. The coupling components include the well known arylamides of 2:3-hydroxy-naphthoic acid, 3-hydroxy-diphenylene-oxide-Z-carboxylic acid and Z-hydroxycarbazole-3-carboxylic acid. They also include diacylacetyl derivatives of aromatic diamines for example diacetoacetyl-orthotolidine. These coupling components can be applied as acid or neutral aqueous dispersions or as alkaline aqueous dispersions which have been buffered to a pH value not exceeding about 10.5.

In the case of the above mentioned ary-lamides and diacylacetyl derivatives of aromatic diamines it is very convenient to apply the diazo component simultaneously therewith and then to subject the material to treatment to diazotise the diazo component on the material and effect coupling of the resulting diazo compound with the coupling component. In the case of some diazo components, particularly aminobenzenes containing but a single benzene nucleus it is found that they are better taken up by the cellulose triacetate at lower temperatures than those at which the coupling components are well taken up. Examples of such diazo components are 0-, mand p-nitraniline, 2:5-dichloraniline, 4-nitro-2-aminoanisole and 5-nitro-2-amino-anisole. In this case, when applying the diazo component and coupling component together, it is advantageous to treat the material with an aqueous liquor containing both components first at a relatively high temperature, e.g. C. or higher and then at a lower temperature, eg a temperature below 100 C. for a period. Thus the material may first be treated at 110 C. or over to ensure good take up of the coupling component and then treatment continued While cooling the dye liquor down to say 5560 C. to ensure good take up of the diazo component.

The term textile material is employed in this specification to include textile fibres (whether short fibres, i.e. staple fibres, or continuous filaments), yarns consisting of or containing such fibres and fabrics woven, knitted or otherwise produced from such fibres or yarns. Thus the dyeing process may be applied to loose staple fibre, to staple fibre or continuous filament yarns, or to woven anarca Z or knitted textile fabrics. Again it may be applied to staple fibres in the form of tops or slivers or other structures such as are the intermediate products in the manufacture of yarns from staple fibres.

The textile fibres of high acetyl cellulose acetate may be those made by a melt-spinning process, especially a process described in United States applications S. Nos. 243,994, filed August 28, 1951, 292,772, filed June 10, 1952, 304,441, filed August 14, 1952, 338,834, filed February' 25, 1953, or in application S. No. 423,743, filed April 16, 1954. In one such process a powdered cellulose ester is urged (e.g. by a rapidly reciprocating tamper) against the side of a heated plate having spinning orifices therein, the powdered ester is fused by the heat applied to the plate, the fused ester is drawn away from the orifices in the form of filaments, and fresh powdered ester is continuously fed to the plate. The spinning orifices may be circular, or they may be in the form of slits or of two or more closely spaced or intersecting holes, as described in United States application S. No. 338,834.

-In another process cellulose triacetate in the form of a coherent rod or a block or tablet of uniform crosssection is pressed axially against a heated plate having spinning orifices therein. Wet and dry spinning methods may also be used to form the cellulose acetate fibres. Thus solutions of high acetyl cellulose acetate in mixtures of methylene or ethylene chloride with methyl or ethyl alcohol or acetic acid, or in acetic acid alone, may be extruded as filaments and set either by means of a coagulating liquid or by an evaporative method. For example solutions of cellulose triacetate in mixtures of methylene or ethylene chloride with acetic acid may be extruded into a coagulating liquid comprising an aqueous alcohol, especially aqueous ethyl alcohol of concentration about 9095%, as described in United States Patent No. 2,657,973, or solutions in acetic acid may be extruded into aqueous acetic acid which may with advantage contain a fairly high proportion of ammonium or an alkali metal acetate, an alkaline earth metal acetate or magnesium acetate, or of some other salt.

Yet another method by which textile fibres of cellulose acetate of high acetyl value may be obtained is the further acetylation of a textile material of cellulose: acetate of lower acetyl value. For instance, yams or fabrics of acetone-soluble cellulose acetate may be further ace-tylated with acetic anhydride in the presence of a diluent such as benzene, and of a basic or acid esterification catalyst such as pyridine, sulphuric acid, perchloric acid or hydrochloric acid, with or without a metal chloride such as zinc chloride or ferric chloride as described in United States Patent Nos. 2,159,011 and 2,159,012.

lif desired [the fibres of high acetyl cellulose acetate may be those having a high safe ironing point such as are described, together with processes for their manufacture, in United States application S. No. 400,798, filed December 28, 1953.

The invention is further illustrated by the following examples.

Example 1 45 lbs. of staple fibre of cellulose acetate (acetyl value about 61.5% 4 ins. staple length and 4.5 filament denier, the filaments having been obtained by dry spirming a solution of the cellulose acetate in a mixture of methylene chloride and methyl alcohol 93:7 by volume, are packed into a cylindrical container and the whole fitted into the aniline) are dispersed in 0.5 gallon of water containing 0.25 ounce of Lissapol C and are added to a fresh bath containing 0.7 lb. of Lissapol C in 70 gallons of water at 40 C. Circulation of this dye liquor through the staple fibre is then commenced and, after sealing the machine, the temperature is raised, by high pressure steam coil, to C., in 30 minutes. This temperature is maintained for a further 2 hours, the direction of flow of the liquor being reversed from time to time. At the end of this time dyeing is complete; the bath is run off and fresh water circulated to rinse the fibre, which is then hydrocxtracted and dried. A full bright red is thus obtained.

In this example the dye specified may be replaced by 0.9 lb. of Eastone Fast Red GLF or of a disperse dye powder containing about 30% of the azo dye from diazotised S-nitrO-Z-arnino-l-methylsulphone and N-beta-hy- .roxyethyl-N-beta-diiluoroethyl-aniline in order to obtain a full red shade. Similarly a blue shade may be obtained by using as the dye 0.4 lb. of a dispersed dye powder containing about 25% of 1-amino-4-p-toluido-anthraquinone or 1-methylamino-4-anilido-anthraquinone.

Example 2 A length of a scoured twill fabric woven from continuous filament yarns made by dry spinning a solution of cellulose acetate of 61.5% acetyl value in a mixture of methylene chloride and methyl alcohol (93 :7 by volume) was provided with calico heard-pieces and loaded on to the rollers of a dye-jig adapted to be operated in an autoclave as hereinbefore described. The dye vessel of the jig was charged with a liquor consisting of water containing 4 grams per litre of Lissapol C (essentially sodium oleyl sulphate), the pH value of the liquor being 7.0 and the ratio of liquor to cellulose acetate being 25:1 by Weight. The loaded jig was then run into its autoclave, the latter closed, and its steam supply turned on. The jigger motion was then started so as to pass the fabric to and firo through the liquor. After 10 minutes the steam pressure had risen to 20 lbs. per sq. in. and the temperature of the liquor to 110 C.

There was then injected into the liquor the following mixture of dispersed dyes dispersed in a litter water Percent Eastman Fast Blue GLF or a dispersed dye powder containing about 30% of 1:S-dihydroxy-S-nitro-4- (p-beta-hydroxyethyl-ani1ido) anthraquinone Eastone Fast Red GLF or a dispersed dye powder containing about 30% of the azo dye from diazotised 5-nitro-2-amino-1-rnethylsulphone and N-betahydroxyethyLN-beta-difluoroethyl aniline 0.4 Dispersed dye powder containing about 30% of 2:4-

dinitro-4-hydroxy diphenyl amine 0.4

Example 3 Scoured cellulose acetate staple fibre of the kind referred to in Example 1 (10 lbs.) is loaded into a pressure dyeing machine in which the dye liquor can be circulated in either direction by means of a pump. The machine is charged with a dye liquor made by pasting 0.3 lb. of Orasol Navy Blue RB with 1 lb. of Turkey red oil, diluting with warm sofit water and straining into suificient Water to make 30' gallons of liquor. The dye liquor is circulated through the staple fibre for 10 minutes at 60- 80 C.; and then for 30 minutes while raising the temperature to C. Dyeing is continued for a further 60 minutes whereupon the dye liquor is cooled and drained off, and the staple fibre washed with water, hydroextracted and dried. A full navy blue shade of excellent fastness properties, particularly to Wet processing, is obtained.

The following dyes may be applied similarly:

(a) Irrgacet Brown 7RL (Geigy), a water-soluble metallised dye.

(b) Zapcn Fast Yellow SRE, a substantially waterinsoluble metallised dye.

(c) The chromium compound (containing about 1 atom of chromium to 1 molecule of dye) of the azo dye from 1 molecule of diazotised 4-nitro-2-amino-phenol and 1 molecule of 1:5-dihydroxy-naphthalene or of the azo dye from diazotised 4 nitro 2 aminophenol and 1- (meta-sulphonamido-phenyl -3 -methyl--pyrazolone.

(d) The chromium obtained by chroming 2 molecules of the azo dye from the diazotised 4-nitro'2-amino phenol and acetoacetic anilide or acetoacetie anilide-msulphonamide with about 1.2 atoms of chromium in the form of alkali metal chromosalicylate.

(e) The cobalt or nickel compound of the azomethine compound made by condensing S-nitro-salicyl-aldehyde with Z-amino-phenol.

Example 4 A padding liquor is made up from the following, all parts being by weight:

Parts Blue disperse dye powder 1.25 Water-soluble methyl cellulose 1.50

Perminal BX (an alkyl-naphthalene sulphonate) 0.20

Dispersol VL (a condensation product of a higher fatty alcohol with several molecules of ethylene oxide 0.20

Water to make 100 The blue disperse dye contains about 30% of the dye mixture obtainable by condensing m-arnino-phenylmethylcarbinol with a mixture of 2 parts of dinitroanthrarufin and 1 part of dinitro-chrysazin as hereinbefore mentioned. The methyl cellulose is one having a viscosity of about 450 centipoises as measured in 2% aqueous solution at 20 C.

A cellulose acetate fabric of the kind referred to in.

Example 2 is padded with the above padding liquor so as to retain 80% of its own weight of the liquor, dried at about 50 C., and steamed for 1 hour with saturated steam at 25 lbs. per sq. in. It is then lightly soaped, e.g. for minutes in 2 g.p.l. soap solution, washed off, and dried. A medium blue shade is obtained.

Example 5 A circulatory type pressure dyeing machine is loaded with 100 parts by weight of cellulose acetate staple fibre of the kind referred to in Example 1. The machine is further charged with a dye liquor made up from Parts Fast Scarlet RC base (4-nitro-2-amino-anisole) 2.0 Naphthol AS.D (o-toluidide of 2:3-hydroxy-naphthoic acid) 2.0

Caustic soda flakes 0.66

Water to make 4000 Lissapol C, 1 g.p.l.

The dye bath is prepared as follows: The base is pasted with one quarter of the Lissapol C and boiled up with a little of the water. The naphthol is pasted with a little water, the caustic soda added as an aqueous solution, and the mixture boiled until the naphthol has dissolved. Both base and naphthol solutions are then added to the remainder of the water and Lissapol C and the whole adjusted to pH 67 with dilute acetic acid.

Circulation of the dye liquor is commenced and the temperature thereof raised to 120 C. (i.e. about lbs. per sq. in pressure); dyeing is continued for one hour at this temperature, and then for a further hour while cooling the dye liquor down to 55 to 60 C. The dye liquor is then removed. The material is then washed by circulating water and then diazotised by circulating 4000 parts of water containing 4 g.p.l. of sodium nitrite and 8 cc. pl. of glacial acetic acid for 1 hour at 20 C. The material is then washed off with water and treated for 30 mins. at 20 C. with 4000 parts of a 1 g.p.l. solution of sodium carbonate and then for 1 hour at C. with 4000 parts of a 1 g.p.l. aqueous solution of soap. Finally the material is rinsed and dried, a full red shade being obtained.

Similar results may be obtained by replacing the base, naphthol and caustic soda by the following:

Parts Fast Red B base (5-nitro-2-amino-anisole) 1.5 Naphthol AS.D 1.5 Caustic soda flakes 0.5

Fast Bordeaux GP base (l-amino-2-nitro-4-methoxybenzene Naphthol AS.OL (o-anisidide of 2:3-hydroxynaph- Using (a) a red shade is obtained, with (b) a Bordeux shade and with (c) a nigger brown shade. In the case of (c) diazotisation is commenced at 20 C. and the temperature raised to 45 C. in 15 minutes and maintained at this for a further 30 minutes.

Having described our invention what we desire to secure by Letters Patent is:

1. Process for effecting the incorporation of a compound selected from the class consisting of dyes and azo dye components in textile material of cellulose acetate of acetyl value at least 59%, which comprises subjecting the material to the action of the compound in presence of a hot aqueous medium at a temperature exceeding C.

2. Process for effecting the incorporation of a corpound selected from the class consisting of dyes and azo dye components in textile material of cellulose acetate of acetyl value at least 59%, said compound having a solubility in water not greater than about 10 mg. per litre at 100 C., which process comprises subjecting the material to the action of the compound in the presence of a hot aqueous medium at a temperature exceeding 100 C.

3. Process for colouring textile material of cellulose acetate of acetyl value at least 59%, which comprises subjecting the material while in contact with a dye, to the actioncof saturated steam at a temperature of a least 4. Process according to claim 3, wherein the dye is a cellulose acetate disperse dye.

5. Process according to claim 3, wherein the dye is a metallised dye.

6. Process for colouring textile material of cellulose acetate of acetyl value at least 59%, which comprises subjecting the material to the action of liquid water containing a dye and at a temperature of at least C.

7. Process according to claim 6, wherein the dye liquid is repeatedly pumped through a mass of the cellulose acetate textile material.

8. Process according to claim 6, wherein the dye is a cellulose acetate disperse dye.

9. Process according to claim 6, wherein the dye is a cellulose acetate disperse dye having a solubility in plain Water at 80 C. of at the most 2 milligrams per litre.

10. Process according to claim 6, wherein the dye is a cellulose acetate disperse dye which, when applied to 1.1 acetone soluble cellulose acetate from an aqueous bath, only yields :full shades in one hour when the dyeing tem- .perature is at least 75' C.

11. Process according to claim 2, wherein the dye is a metallised dye.

12. Process according to claim 2, wherein the dye is a metallised dye, free from sulphonic groups, in which the metal is of atomic weight between 50 and 66 and the parent dye is an azo dye in which an azo group unites two carbon atoms each of which is directly attached to a carbon atom carrying a hydroxyl group.

13. Process according to claim 12, wherein the metallised dye contains a sulphonamide group.

14. Process according to claim 12, wherein the metallised dye is a chromium compound and contains about one atom of chromium to two molecules of the parent dye.

15. Process for elfecting the incorporation of an arylamide of 2:3-hydroxynaphthoic acid in textile material of cellulose acetate of acetyl value at least 59%, which comprises subjecting the material to the action of liquid water containing the arylamide and at a temperature of at least 110 C.

12 16. Process according to claim 15, wherein the water contains also a diazotisable.aminobenzene containing but a single benzene nucleus and the treatment is carried out first at a temperature of at least 110 C., and subsequently at a temperature below 100 C. to permit take up of the aminobenzene by the material.

"References Cited in the file of this patent UNITED STATES PATENTS 2,190,825 Camille et al Feb. 20, 1940 2,263,387 Honk et 'al. Nov. 18, 1941 2,837,437 Finlayson et al. June 3, 1958 OTHER REFERENCES 

1. PROCESS FOR EFFECTING THE INCORPORATION OF A COMPOUND SELECTED FROM THE CLASS CONSISTING OF DYES AND AZO DYE COMPONENTS IN TEXTILE MATERIAL OF CELLULOSE ACETATE OF ACETYL VALUE AT LEAST 59%, WHICH COMPRISES SUBJECTING THE MATERIAL TO THE ACTION OF THE COMPOUND IN PRESENCE OF A HOT AQUEOUS MEDIUM AT A TEMPERATURE EXCEEDING 100*C. 